Apple and Google will team up on technology intended to reduce the spread of Covid-19 by warning users if they have been near an infected person. In a rare partnership between the two Silicon Valley tech rivals, the companies will introduce contact-tracing technology that will allow smartphone users on the iOS and Android platforms to opt into the system. Users will get an alert if they have been exposed to a person who tested positive for Covid-19 and receive information on their phones from health authorities on what to do next, Apple and Google said on April 10. "All of us at Apple and Google believe there has never been a more important moment to work together to solve one of the world’s most pressing problems," the companies said. "Through close co-operation and collaboration with developers, governments and public health providers, we hope to harness the power of technology to help countries around the world slow the spread of Covid-19 and accelerate the return of everyday life." The technology has the potential to reach a huge number of the world's population, if users agree to opt into the system. Between them, Apple's iOS and Google's Android platforms have around three billion users, about one third of the world's population. Governments are scrambling to contain the spread of the deadly virus through contact tracing – a process in which health officials go to people in recent contact with an infected person and ask them to be tested or quarantined – by adopting technology that can speed up the process. The fast-spreading virus had infected about 1.7 million people globally and killed over about 103,000 as of Saturday, according to the <a href="https://coronavirus.jhu.edu/map.html">Johns Hopkins University's coronavirus tracker</a>. Around of 377,000 people have recovered. Apple and Google will roll out their contact-tracing software in two steps while underscoring the "strong protections" around user privacy. In May, the companies will introduce software that allows Android and iOS smartphones to exchange information using apps from public health authorities. These official apps will be available for users to download via their respective app stores. In the second step, during the coming months Apple and Google will add Bluetooth-enabled contact tracing directly on to their operating systems. This means more users who opt in can gain access to the system. However, the use of contact-tracing technology has sparked global privacy debate as health information of billions gets shared on mobile devices. Apple and Google stressed that their technology protects users' privacy and explicitly requires their consent. "Privacy, transparency and consent are of utmost importance in this effort, and we look forward to building this functionality in consultation with interested stakeholders," the two companies said. "We will openly publish information about our work for others to analyse." The contact-tracing system does not collect personally identifiable information or user location data. The list of people a smartphone user has been in contact with never leaves their phone and people who test positive are not identified to other users, Google or Apple, the companies said. The tool "will only be used for contact tracing by public health authorities for Covid-19 pandemic management", it said.